Developments in the field of dialogue systems for use in consumer households can be expected to lead to the widespread use of such dialogue systems in homes in the near future. A home dialogue system can be realized as a kind of ‘robot’, perhaps even with human or animal appearance or characteristics, and can be used to perform tasks for the user. Such tasks might be of a practical nature, such as cleaning a floor or tidying up, and can serve to assist a user in everyday situations. To increase the practical usefulness of a home dialogue system, such a device will be able to autonomously move about in its environment. It is likely that such an autonomous system, or autonomous device, will avail of a certain ability to ‘learn’ from its surroundings, and that it continuously collects or records audio and video data. For example, the autonomous device might continuously record video data which are then processed so that the autonomous device can determine if there are any items in its surroundings that need to be tidied away, or if it can ‘see’ an item that the user has sent it to fetch. Audio data can also be continuously recorded and analyzed so that the autonomous device can determine if it is being addressed and can ‘understand’ what is being said.
Such analysis and processing of audio and video data requires a certain amount of electronic hardware such as speech and image recognition systems, which can be bulky. On the other hand, incorporating such hardware into the autonomous device will make this relatively large and cumbersome, and correspondingly expensive. Therefore, since it is easy to transmit audio and video data over a wireless network to, say, a personal computer (PC) having sufficient processing power, it would suffice to simply record the data using cameras and microphones, and to transmit the data for distributed processing, perhaps in a compressed format, to the PC in the vicinity. The PC can then process the data and provide the autonomous device with any relevant results. The autonomous device can thus be realized in a more compact way, which is also an economic consideration, particularly when there are more than one autonomous device in use in a certain environment.
The continual recording of audio or video data might be undesirable to a user for a number of reasons. For example, it might well be unacceptable to have images or audio recordings of a user in a private situation being transferred to a potentially insecure medium where they are vulnerable. With relatively little effort, a person with ill intent can tap into and record any data being transferred over a wireless network, which is certainly undesirable from the user's point of view. Data can also be retrieved relatively easily from a hard disk, even after they have been deleted. However, even if private data recorded by the autonomous device is not misappropriated, merely the feeling of being continually ‘watched’ or ‘observed’ by the autonomous device can be uncomfortable to a user. This might apply even if the autonomous device is simply gathering video or audio data for the purpose of fulfilling its assigned tasks. Since it is foreseeable that many homes in the near future will be equipped with such autonomous devices, this problem will be experienced by a growing number of users. One way of dealing with this problem might be for the user to issue a spoken command to stop the autonomous device from transferring audiovisual data to a host computer. However, the user must be aware that the autonomous device has entered a private area, and the user must also remember to issue the appropriate command at a later time to allow the autonomous device to resume transmission. Besides, such commands might not always be practicable, for example if the user is in the shower, or asleep.
Therefore, it is an object of the invention to provide a straightforward way of ensuring the privacy of a user of an autonomous device.